Make sure that the pedal and the control BOTH have the same air pressure rating. If not you will either have no throttle or a wide open throttle during application. The part number on the housing will tell you. Experience speaking here.

Don, I just received a Williams Air Control foot treadle with the numbers (WM-453-B) on the body. Two weeks ago I purchased the ebay listing of the modulator I will call it that mounts at the engine that is also mentioned in this thread above. This is a very, very good looking modulator too I might add and the price is wonderful too. I plan to get another just for kicks or in case needed on the road and have a spare for the price. The instructions for the modulator mounted on the engine says to use (60 psi) but I do not have any instructions for the foot treadle I just received today. With the knowledge you now have in your opinion should I use a pressure regulator for 60 psi or use the full pressure to have control of the foot pedal for speed of the engine etc? so with the information I have given you, would you recommend full air pressure of the 1/4" line or 60 PSI?? Also, would you run 3/8" or 1/4" line from the front of the bus to the back Governor modulator??Thanks ahead of timeGary